Pernik
Immediately next to Sofia, the province of Pernik is marked by the Struma River, the vast Pernik Valley and Mount Vitosha. Having started off as a Thracian site in the 4th Century BC, the area was largely Romanised towards the 1st Century AD, and along with the establishment of the Bulgarian state, it further grew in significance. During the Middle Ages, it was here that Tsar Samuil led his campaign against Byzantium. Having fallen under the Ottomans in the late 14th Century, Pernik became a mining area, and its major town is still best known for its metallurgical industry.